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Pressure Transducers Allow Variable Frequency Drive Control in Machinery and Factory Automation

Pressure Transducers Allow Variable Frequency Drive Control in Machinery and Factory Automation

Variable frequency drives, or VFDs, control an electric motor by modifying the power input frequency to the electric motor. VFDs used in conjunction with electrically driven pumps control the flow rate and the output pressure of the pump with continuous pressure.

Pressure transducers are a significant part of this process. Pressure transducers monitor the pressure at the pump outlet at the area of interest and interface with a VFD-controlled pump to indicate when pressure or flow rate should be increased or decreased as necessary.

The role of pressure transducers

Pressure transducers are used for VFD control in machinery and factory automation to:

  • Monitor pump intake pressure
  • Monitor and control pump output pressure
  • Monitor and control end location pressure, such as with reservoirs and water systems

Electric motor VFD control in machinery and factory automation applications requires pressure transducers to be compatible with compressed air, potable water, sewage, and other moderately corrosive media.

Common uses of VFDs 

VFD pumping systems excel where continuous monitoring of pressure to minimize overshoot and undershoot of desired pressures is necessary, such as in:

  • Water lift systems: Transfers water supply from lower to higher elevation levels since conventional gravity-fed systems with water tower cannot apply necessary pressure.
  • Clean water systems: Transfers water supply to, through, and from water treatment facilities.
  • Sewage pumping systems: Transfers sewage to processing plants where fluids can be filtered, cleaned, and released to the environment.
  • Reservoir management systems: Includes water towers, where sudden draws of water decrease the outlet water pressure of the tower, requiring immediate refilling.
  • Compressed air systems: Includes shop air supply, where constant, reliable air pressure is required.

WIKA pressure transducers used for VFD control

The following WIKA electronic pressure transducers have been designed for reliability, accuracy, and quality in machinery and factory automation electric motor applications like VFD control:

Pressure transmitter model A-10

Pressure transmitter model A-10